Sunday, October 28, 2012

Carex Like You Mean It

Grasses and grass-like plants are overlooked by many gardeners – they are plain and messy looking compared to clipped lawns and don’t have showy flowers. Wait, they have flowers? Who knew?
Carex laxiculmis flower, in April

While many folks might consider them all “grasses”, they aren't; For the most part they fall into the familiar 3 groups: sedges, rushes and grasses. In fact you might have heard the familiar rhyme (which comes in several forms). The first one is my favorite:

“Sedges have edges; rushes are round; grasses are hollow right up from the ground”. 

Another version of this poem is, "Sedges have edges, rushes are round, grasses have nodes and willows abound." Or “Sedges have edges, rushes are round, grasses are hollow, what have you found?” And one more that you might find useful: “Sedges have edges, rushes are round, and grasses have joints.” All of these are meant to offer clues for identification.

Carex laxiculmis leaf blade

I have lately become very fond of sedges which are known botanically as Carex.  More of them have found their way into cultivation, and I was charmed into purchasing a few of them. But I have also learned how to identify them and have been able to find several different species in the wild and in my own yard (the wooded section).

So what does it mean that “sedges have edges”? Several sources describe the arrangement as having “triangular stems” – there are 3 edges as if the blade was V-shaped. One might consider that one edge is a ridge that runs down the center. Of course you can also identify it by ruling out the other two: the leaves are not round, so it’s not a rush. And it’s not a grass because there are no joints and the leaf is not hollow.

Garden worthy features of Carex include being mostly evergreen, being shade tolerant, growing in a clump form, and being fairly deer resistant. (But not cat resistant – they will try to eat them as they think they are grasses too.) Take note of what I said  – deer resistant. Yep, I’m growing them right out in the open and they have not eaten them. They have eaten the Virginia creeper vine and the azalea right next to them, but they have not eaten the Carex.

Carex laxiculmis 'Bunny Blue'
The first one that I got was a nursery purchase. The common name is spreading sedge and it is Carex laxiculmis 'Bunny Blue'. This is an arrangement of 3 plants purchased as quarts. I liked the blue-green color, and it has been a beautiful addition to the more cultivated area in my garden. It has spread a little, and I have been able to easily pot up the babies for a donation to the GNPS spring plant sale.

Carex plantaginea

Shortly thereafter a friend gave me two small pieces of Carex plantaginea that she rescued in North Carolina with the native plant society. What a handsome plant! The quilted texture of the leaves is a great addition to the garden, and the small plants are now robust clumps (but no babies in sight).

As you can see, Carex are handsome plants. There are hundreds of different species native to the United States, many native to the southeastern US. Across the different species there are a range of different leaf colors, leaf widths and lengths, and growing conditions. Many are shade tolerant but others grow in the sun, especially morning sun. They are found in habitats that  range from dry to wet and all in between.

Unknown Carex

Now that I am more aware of sedges, I see a variety of species in the woods wherever I go.  Here is one that popped up in a pot of Trillium that someone gave me. It's a keeper. When it flowers this spring, I hope to identify it.

Carex is one suggestion if you're looking for a native replacement for Liriope, a non-native plant often used for edging. You can see the resemblance.  

Carex is #6 on the list of perennials that support native Lepidoptera (butterflies and moths) as a host plant, so the usage of it instead of a non-native plant is even more beneficial.

Carex pensylvanica

So I hope you will consider using Carex in your garden.  I think if you try one, you will soon become as enamored as I am. The many varieties of texture and color are sure to offer you a chance to use several species.

Now I think I'll go outside and plant this last one that I bought ... the fine bladed texture of Carex pensylvanica was irresistible, and I heard it does well in dry shade. I have just the place ....


  1. I'm a big fan of carex myself, Ellen. My yard is home to so many that just occur naturally. This is great information you have provided for those who need to go the nursery purchase route.

    I only began my quest of identification this year and have had some success. Love the poem. I only had heard the first line "sedges have edges". Your highlighting the additional verse has been added to my memory bank. I'm going with the "what have you found" version.

    Again great information and advocacy for the too often unheralded of our gardens

  2. Carex Bunny Blue is a trademark name. It's real cultivar name is 'Hobb'

  3. Ellen, I need to write a newsletter article for our HOA publication. (I just became the Landscape Committee Chair - by default.) I came directly to your blog to search for "deer resistant" and found this great Carex article. As always, thank you so much for assembling this invaluable collection of knowledge on native plants.